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Biolistic Particle Gun, Prototype II

Biolistic Particle Gun, Prototype II

This object is the second prototype of a biolistic gene gun produced by John Sanford, Ed Wolf, and Nelson Allen at Cornell University in Ithaca, New York. Biolistic gene guns are used to genetically transform plants by shooting microprojectiles (tiny bullets) covered in DNA into plant cells. Prototype II incorporated several new features, including a plunger that accelerated microparticles using gunpowder rather than air. It also featured a vacuum chamber to reduce drag on the particles from air resistance. Sanford’s post-doctoral student Theodore Klein used this model in extensive experiments to calibrate the biolistic gene gun technology for optimal results.

Gene guns were the brainchild of plant geneticist Dr. John C. Sanford, who spent much of the early 1980s looking for a way to insert foreign DNA into plant cells in order to create transgenic plants. At the time, the most successful process for doing this relied on a species of bacteria. The method, however, only worked for certain plant species and was not successful with important crops like wheat, rice, or corn. Sanford considered a variety of techniques, including piercing cell walls with a laser, but it was not until he teamed up with Dr. Edward Wolf of the Cornell engineering labs, that he hit on a method that worked.

Following discussions with Wolf, Sanford mentioned a new idea- partially inspired by his ongoing fight against squirrels in his yard- a biolistic gene gun. “Biolistic” is a combination of the words “biology” and “ballistics.” Working on principles similar to a BB gun, the gene gun would blast cells with microprojectiles covered in DNA.

To create the first prototype, Wolf brought in Nelson Allen, head machinist in the engineering lab, to modify a standard air pistol so that it could accelerate extremely small particles of tungsten into whole onions. Allen became integral in bringing Sanford’s ideas to life, producing the multiple prototypes the team designed as they perfected the technology. His interest in the project was personal. His daughter died of leukemia at the age of 20, and Allen hoped that eventually the technique could lead to medical advances.

Sanford, Wolf, and Allen spent the 1983 Christmas break trying out the gun and splattering themselves with exploded onion parts. After proving that individual onion cells could survive bombardment by microprojectiles and that the microprojectiles could be used to introduce DNA into the cells, the team filed for a patent. They also set to work designing a second prototype, this object, as the air power used in the first prototype proved too destructive to samples at close range and caused particles to lose their acceleration over longer ranges. It was also the model used in the first successful stable genetic transformation of plant cells by biolistics. The results were reported in Nature in 1987.

Prototype III (see object 1991.0785.01.1) was a further improvement, featuring a surge tank (see object 1991.0785.01.2) to collect debris from the firing. It incorporated many of the features that would be used in the first commercial models.

Eager to see the technology result in practical application, but unable to find any interested investors, Wolf and Sanford created their own business, Biolistics, Inc, in 1986 to sell gene guns to other researchers. Their product was met with great enthusiasm, Wolf and Sanford were “hounded” for orders from the scientific community. A commercially friendly design, similar to prototype III, was perfected by Nelson and the guns were fabricated by Rumsey-Loomis Co. of Ithaca, N.Y., a local machine shop. In April of 1989, Wolf and Sanford sold the business to DuPont, which was able to market the gun on a larger scale. Sanford's final update to the technology was the replacement of gunpowder with helium cartridges. A gun with these features was still available on the market from Bio-Rad as of 2012.